Method and apparatus for measuring deformations of test samples in testing machines

US4836031A · kind A · utility

Assignee

• Carl Schenck AG · DE

Inventors

• Ralf Jatho · Seeheim-Jugenheim, DE
• Gerhart Hintz · Roßdorf, DE
• Guenter Keller · Bensberg, DE

Key dates

• Filing date: Jun 16, 1988
• Grant date: Jun 6, 1989
• Expiry date: Jun 16, 2008

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2203/0647
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

In a method and apparatus for measuring deformations of test samples in testing machines, a test sample (4) is clamped into force transmitting units (10, 11). A light source (1) emits a light beam (2) which is reflected from at least one mirror (6, 6') arranged on the force transmitting units (10, 11) to impinge upon a position detector (7) which generates an output signal. The output signal is input to an electronic evaluating circuit (8) to determine the location or rather the location movement of the point of impingement of the light beam on the position detector. Preferably, but not necessarily, each force transmitting unit (10, 11) includes its own mirror (6, 6'), whereby the light beam (2) emitted by the light source (1) is reflected in sequence by the first mirror (6) of the first force transmitting unit (10) onto a second mirror (6') of the second force transmitting unit (11) and then onto the position detector (7). These steps and elements measure a test sample deformation and/or a deformation velocity with a high accuracy and in a simple manner, especially in fast tensile rupture testing machines.